Add the life-cycle chapter, including _XEMBED_INFO property, and the XEMBED_MAPPED flags.

Define the data2 for XEMBED_EMBEDDED_NOTIFY to be the protocol version in use.

Replaced XEMBED_GRAB_KEY scheme for handling accelerators with XEMBED_REGISTER_ACCELERATOR.

Removed text "This also means that the client has to prepare for becoming visible anytime without filing a map request itself" from the description of XEMBED_EMBEDDED_NOTIFY".

Added text about the independence of FOCUS_IN/OUT and ACTIVATE/DEACTIVATE to the description of XEMBED_WINDOW_ACTIVATE / XEMBED_WINDOW_DEACTIVATE.

Added note about fields in WMNormalHints not necessarily being obeyed by embedders.

Removed mention of XEMBED_PROCESS_NEXT_EVENT, which is no longer part of the protocol.

Added definitions of "Active" and "Focused" to the definitions section.

Added issues and change history sections.

Lots of textual editing for clarity, style consistency.

Converted to docbook format.